This invention relates to a surgical instrument and more particularly to a combined laparoscopic scissors and forceps device.
Laparoscopic surgery is used to provide a wide variety of surgical procedures on a patient""s abdomen. The application of laparoscopic methods continues to grow as techniques are refined and the associated surgical instruments are improved. Patients benefit from laparoscopic procedures because the methods employed minimize the amount of trauma associated with a given procedure. Hence, patient survival is enhanced and recovery times are decreased.
Prior art laparoscopic surgical instruments typically include a handle, a 33 centimeter length, 5 millimeter diameter shaft which can be inserted through a cannula placed in a patient""s abdominal wall, and scissors or tissue grasping jaws (e.g., forceps) extending from the end of the shaft.
In some cases, laparoscopic graspers, and/or scissors and some other types of instruments have the ability to apply RF energy in order to locally vaporize tissue and thereby cut through it or to coagulate blood vessels. There are two common ways in which the RF energy is applied. In either method, current travels between two electrodes. In monopolar instruments, the surgical instrument serves as one electrode and the second electrode is a large surface area electrode placed on the patient. In bipolar instruments, both electrodes are disposed on the surgical instrument in close proximity to one another.
Many conventional laparoscopic surgical instruments tend to be clumsier than those used in conventional surgery. As explained above, in laparoscopic surgery, the surgical instruments are inserted through a cannula placed in the patient""s abdominal wall. To keep patient trauma to a minimum, only a limited number of cannula are employed for a given procedure. Often, using existing surgical instruments, the instruments must be repeatedly removed from the cannula and replaced with different instruments and removed and replaced again. This process of repeated instrument exchanges greatly increases the time it takes to perform a given medical procedure.
Two commonly used laparoscopic instruments are scissors and tissue graspers. Scissors are used to dissect tissue, transect ligated vessels or other bodily ducts (such as fallopian tubes), trim sutures and ligatures and to perform other cutting functions. Graspers or forceps are used to grip and manipulate tissue and to perform a variety of blunt dissecting procedures. Tissue is either grasped and pulled away from substrate tissue to which it is loosely connected or the blunt tips of the closed graspers are inserted between loosely connected tissue strata and then the tips are forced apart separating the tissue strata. The operation of ordinary scissors and forceps is very familiar to surgeons and non-medical personnel alike and their function and operation are somewhat intuitive. This fact remains true when scissors or forceps are incorporated into a traditional laparoscopic instrument.
Traditionally, when tissue cutting procedures are required, a scissors type laparoscopic instrument is used. When tissue grasping procedures are required, a forceps type laparoscopic instrument is used. Thus, the surgeon must either employ two cannulas or switch instruments depending on whether cutting or grasping procedures are required.
To overcome this problem, those skilled in the art have developed surgical instruments with detachable scissors and forceps end assemblies, and surgical instruments with combined scissors and forceps end assemblies.
For example, U.S. Pat. No. 5,893,875 discloses a surgical instrument with replaceable end effector assemblies. To switch between tissue cutting and grasping procedures, however, the surgeon must withdraw the instrument from the patient and replace the scissors end effector assembly with a forceps end effector assembly.
This practice of instrument exchange greatly increases the time it takes to complete a given surgical procedure. An attempt to overcome this problem is disclosed by a combined cutting blade/forceps end assembly. Pivoting jaws 10 and 12, FIG. 1, are configured as forceps and blade 14 attached to pivoting jaw 10 allows the surgeon to cut the tissue. See U.S. Pat. No. 5,456,684. In another prior art device, one portion of each operable jaw 20, 22, FIG. 2, includes scissors portions 24, 24xe2x80x2 and a forceps portions 26, 26xe2x80x2, respectively. See U.S. Pat. No. 5,908,420.
In another prior art device, cutting blade 30, FIG. 3, is extendable between forceps 32 and 34. See U.S. Pat. No. 5,496,317. In still another device, blade 40, FIG. 4 is disposed between forceps 42 and 44. See U.S. Pat. No. 5,573,535. See also the BiCoag(copyright) bipolar cutting forceps available from Everest Medical, 13755 First Avenue North, Minneapolis, Minn. 55441-5454.
All of these devices suffer from the fact that the scissoring and grasping capabilities are poorer than that which is available separately in single function devices.
Moreover, surgeons will not generally use any surgical instrument which does not operate in the way expected or in a way which is not intuitive. When conventional surgical devices with scissor grips are used, it is expected that the action of closing the scissor grips closes the scissor blades for tissue cutting or brings the forceps jaws together to grasp the tissue between them. This is not the case with the device discussed above. For example, in order to use the device disclosed in U.S. Pat. No. 5,573,535, the surgeon uses a scissor grip to operate the forceps jaws but must operate a separate lever to effect distal movement of the blade member to cut tissue. See the ""535 patent, col. 5, lines 43-66.
Other shortcomings of prior art devices include their complexity and high manufacturing costs. High manufacturing costs are especially important in surgical devices because they are often used in connection with one procedure on a given patient and then discarded.
It is therefore an object of this invention to provide a surgical instrument with an end assembly which includes both a pivoting scissor blade and a pivoting forceps jaw.
It is a further object of this invention to provide such a surgical instrument which eliminates the need for the surgeon to switch instruments during a given medical procedure.
It is a further object of this invention to provide such a surgical instrument which eliminates the need for additional cannulas inserted through a patient""s abdominal wall.
It is a further object of this invention to provide such a surgical instrument in which the scissoring and the grasping capabilities are as good as that which is available separately in single function devices.
It is a further object of this invention to provide such a surgical instrument which operates in the way expected and whose use is intuitive.
It is a further object of this invention to provide such a surgical instrument which does not require the surgeon to operate separate levers in order to effect tissue cutting or tissue grasping procedures.
It is a further object of this invention to provide such a surgical instrument which is simple in design and which can be manufactured at a low cost.
It is a further object of this invention to provide such a surgical instrument which allows surgeons to remain focused on the operating procedure and not distracted by instrument exchanges or the need to operate separate levers.
It is a further object of this invention to provide such a surgical instrument which results in medical procedures performed in a shorter period of time.
It is a further object of this invention to provide such a surgical instrument which can be accommodated by a five millimeter cannula.
It is a further object of this invention to provide such a surgical instrument which can be easily and ergonomically operated by one hand. It is a further object of this invention to provide such a surgical instrument which can be equipped with bipolar or monopolar RF energy subsystems for electrosurgical procedures.
It is a further object of this invention to provide such a surgical instrument which can be readily equipped with surgical end effectors other than scissors and tissue graspers.
It is a further object of this invention to provide a surgical instrument with an end effector that may be rotated relative to its handle.
The invention results from the realization that a more intuitive, ergonomic, easier to use, and easier to manufacture surgical instrument which performs both tissue cutting and grasping procedures without the need to replace the end assembly and which incorporates both scissors and forceps (or other end effector combinations) jaws in a single end assembly can be effected by a uniquely configured end assembly with a fixed central member that functions both as a scissor blade and a forcep jaw disposed between a separate pivotable scissor blade and a separate pivotable forcep jaw and by a linkage assembly connected between the end assembly and a pair of scissors grips which allow the surgeon to open and close the scissor blades in one range of motion and to open and close the forceps jaws in another range of motion.
This invention features a surgical instrument comprising a handle assembly, a shaft connected on one end to the handle assembly, and an end assembly extending from the other end of the shaft. The end assembly includes a fixed member including on one portion thereof a fixed scissor blade and on another portion thereof a fixed forcep jaw. The end assembly also includes a pivotable scissor blade for cutting tissue between the fixed scissor blade and the pivotable scissor blade and a pivotable forcep jaw for grasping tissue between the fixed forcep jaw and the pivotable forcep jaw.
The fixed forcep jaw and the pivotable forcep jaw may include serrations thereon. The fixed member is typically disposed between the pivotable scissor blade and the pivotable forcep jaw. In the preferred embodiment, the pivotable scissor blade is disposed above the fixed member and the pivotable forcep jaw is disposed below the fixed member. Thus, the fixed forcep jaw is on a lower portion of the fixed member and the fixed scissor blade is on an upper portion of the fixed member.
The handle assembly preferably includes spaced scissor-like handles. Typically one handle is pivotably attached to the handle assembly and has a predetermined angular range of motion with respect to the handle assembly. The shaft then includes a linkage assembly which opens and closes the scissor blades during one portion of the angular range of motion of the pivoting handle and opens and closes the forcep jaws during a second portion of the angular range of motion of the pivoting handle. In one embodiment, a scissor blade push rod and a forcep jaw push rod are slidably disposed in the shaft. The pivotable scissor blade is pivotably attached on one side of the fixed member and the pivotable forcep jaw is pivotably attached on another side of the fixed member. In a preferred embodiment, the scissor blade push rod is connected on one end to a scissor blade link which is connected to the pivotable scissor blade and the forcep jaw push rod is connected on one end to a forcep jaw link which is connected to the pivotable forcep jaw.
In the preferred embodiment, the scissor blade push rod is connected on one end to a scissor block slidably disposed in the handle assembly. The scissor block includes a projection extending into a first cam groove. The jaw push rod is connected on one end to a jaw block also slidably disposed in the handle assembly. The jaw block includes a projection extending into a second cam groove. The cam grooves are typically formed in an ear of the pivotable handle.
Electrical conductors may be incorporated and connected on one end to the fixed member and the pivotable forcep jaw for coagulating tissue.
The invention also features a surgical device comprising a handle assembly; a shaft connected on one end to the handle assembly; and an end assembly extending from the other end of the shaft, the end assembly including a fixed member including on one section thereof a fixed portion of a first surgical instrument and on another section thereof a fixed portion of a second surgical instrument. The end assembly also includes a pivotable portion of the first surgical instrument pivotably attached to the fixed member and disposed to cooperate with the fixed portion of the first surgical instrument to perform a first type of medical procedure. The end assembly also includes a pivotable portion of the second surgical instrument pivotably attached to the fixed member and disposed to cooperate with the fixed portion of the second surgical instrument to perform a second type of medical procedure.
In one embodiment, the fixed portion of the first surgical instrument is a fixed scissor blade and the pivotable portion of the first surgical instrument is a pivotable scissor blade. Also, the fixed portion of the second surgical instrument may be a fixed forcep jaw and the pivotable portion of the second surgical instrument may be a pivotable forcep jaw.
In another embodiment the handle member includes means to allow rotation of the end assembly and shaft relative to the handle assembly.
An end assembly for a surgical instrument in accordance with this invention features a fixed member including on one portion thereof a fixed scissor blade and on another portion thereof a fixed forcep jaw; a pivotable scissor blade pivotably attached to the fixed member for cutting tissue between the fixed scissor blade and the pivotable scissor blade; and a pivotable forcep jaw pivotably attached to the fixed member for grasping tissue between the fixed forcep jaw and the pivotable forcep jaw.